1. Field of the Invention
The present invention relates to a telephone answering machine.
2. Description of the Related Art
Prior art telephone answering machines are connected to communication lines such as ISDN (Integrated Service Digital Network) or a general public network which is supposed to be inaugurated in a couple of years. The ISDN is a high-capacity high-speed data transmission system which allows a called party to be informed of calling party information including calling party telephone numbers when the data is transmitted. The general public network, on the other hand, allows a called party to be informed of the calling party information when the data is received. These conventional telephone answering machines automatically catch a communication line in response to a receiving signal which is sent from the communication line, and transmit a response message to the communication line. When the transmission of the response message is completed, some of the conventional telephone answering machines record a message from the calling party which is sent through the communication line, and others do not record the message. Another conventional telephone answering machine stores calling party information which is reported when the data is either transmitted or received, thereby identifying each calling party who called during the called party's absence.
However, these conventional telephone answering machines have the following two drawbacks. When a calling party calls the called party's telephone more than once, the calling party information is stored every time and all the messages of the same calling party are recorded. This wastes the capacity of a semi-conductor memory which stores calling party information and records calling parties' messages, or the capacity of a magnetic tape which records calling parties' messages. Consequently, the amount of calling party information to be stored and the number of messages to be recorded are limited. In addition, calling parties' messages are played back in the order in which they are recorded, so that when several messages from the same calling party are recorded with interruption of a message of another calling party, it is troublesome for the called party to understand all the messages.